μαρτυροποιέω
From LSJ
Δεῖ τοὺς φιλοῦντας πίστιν, οὐ λόγους ἔχειν → Non bene stat intra verba amicorum fides → Vertrauen müssen Freunde sich, viel reden nicht
English (LSJ)
A produce evidence, PLips.40 iii 14 (iv/v A.D.), Gloss.: —also in Med., call to witness, Corn.ND16. II mostly in Med., testify, certify on oath, IG9(1).61.8 (Daulis, ii A.D.), Mitteis Chr.242.3 (ii A.D.), Sammelb.5217.20 (ii A.D.), etc.